Sampling of organ tissue or the like is often required to help in the diagnosis and disease staging of a patient. Numerous tools and devices for such purpose have been disclosed, which typically comprise a narrow elongated guide or sheath through which a sampling needle or blade is advanced to take a sample, and then retracted. The tools are commonly designed for taking a sample from tissue located axial to the tool, i.e. in front of (in continuation with) the end of the tool.
To allow taking a sample lateral to the sampling device, WO 2006/015,302 (Schomer/X-Sten) discloses a method for treating stenosis in a spine including inserting a tissue removal tool into tissue in the working zone. In some embodiments, the tissue removal tool has a side aperture from which a resilient tissue-engaging hook with a pre-configured in a curvilinear shape is retained within the tool by an outer cutting member. When the cutting member is retracted, the curved shape of the hook urges the hook's outer end to extend outward through the side aperture. This activity is particularly shown in FIGS. 10-14, especially FIG. 12 of the publication.
US 2002/183,758 (Middleton) discloses a tissue cavitation device which can be used to remove tissue, including lateral to the longitudinal axis of the device. A flexible cutting element is extendable from the distal end (away from the longitudinal axis) of a shaft/insertion tube of the device. The cutting element is spring loaded like a leaf spring so that upon distally exiting from the shaft/insertion tube, the cutting element lateral returns a bent or curved shape and thus extends both longitudinally and laterally from the distal end of the shaft. This feature is particularly well shown in FIGS. 2B and 4C.
The lateral sampling of the aforementioned publications, being based on spring loading (biasing) of the sampling element tends to result in a sweeping movement of the sampling element when the element exits the guide (sheath, shaft), which may cause undesirable collateral damage to the tissue. Further, such designs may require penetration of the guide itself into the tissue to be sampled and not merely the blade or other such sampling element. Moreover, the penetration strength of the sampling element/blade is mainly and perhaps merely a result of the biasing.